This invention concerns refractory lining repair. More specifically, it concerns an apparatus for the monitoring and repair of the refractory lining of metallurgical vessels in the vertical position at elevated temperature.
Apparatus, such as those disclosed in U.S. Pat. Nos. 3,797,745 and 3,799,445, are known for the gunning of the vertical walls of refractory vessels such as ladles and electrical steelmaking furnaces by remote control while the vessel is at elevated temperature. These devices, however, are limited to applications where the operator can safely see the area being gunned. A great need still exists for a unit which can be used under conditions, such as with upright basic oxygen furnaces between heats, where the operator cannot approach and observe the lining repair area. It is therefore a primary objective of the present invention to provide a gunning apparatus for the repair of such vessel linings at or near steelmaking temperature which visually monitors the repair operation and thereby allows for a more effective and efficient application of the repair material.
A nonvisual means of repairing refractory linings of metallurgical vessels in which the damaged zones of the lining are repaired using a spraying nozzle controlled by a water-cooled microwave scanner is disclosed in German Offenlegungsschrift No. 2626421.
Visual monitoring of hot refractory linings is disclosed in U.S. Pat. No. 3,609,236, in which a cooled and purged television camera and lens assembly is mounted on a powered operator adjacent an apertured hazardous chamber such as a high-temperature furnace, and in German Offenlegungsschrift No. 2641382, in which a water-cooled television camera housing with air-cooled zoom lens is moveably supported to observe the interior surface of refractory chambers such as a coke oven at temperatures of up to 1200.degree. C.